Method and system to control flow from individual nozzles while controlling overall system flow and pressure

ABSTRACT

A method and system has been developed to individually control the flow of liquid products from any nozzle within a plurality of nozzles using pulse width modulated solenoid actuated valves. The method and system simultaneously controls multiple flow and shutoff related inputs including but not limited to turn radius, nozzle overlap, swath reduction, nozzle spacing, fence row rates, wheel track rates, etc. The method and system will also simultaneously accept one or more external inputs from commercially available application rate control devices where other rate and shutoff inputs may be used, for example, variable rates per boom section based on GIS maps or multiple in-field sensors along the boom. The method and system further incorporates the artificial manipulation of commercial rate controller inputs and outputs to facilitate these individual nozzle control features and benefits without compromising the overall system flow control performed by the commercial rate controller.

RELATED APPLICATIONS

The present application is a continuation of prior U.S. patentapplication Ser. No. 12/533,486, filed on Jul. 31, 2009, which is, inturn, based upon and claims priority to U.S. Provisional PatentApplication No. 61/085,772, filed on Aug. 1, 2008, both of which arehereby incorporated by reference herein in their entirety for allpurposes.

BACKGROUND

Commercially available independent flow and pressure control systems fordispensing agrochemicals onto fields exist and are well documented inthe prior art. These systems utilize a plurality of solenoid actuatedvalves that pulse according to a on/off ratio which determines the flowfrom the group of nozzles at any given pressure. Therefore, the pressureof the system can be controlled for such parameters as droplet size,system flow capacity, stream dynamics, injection penetration, etc.,while the flow of the system is independently controlled for suchparameters as application rate (gallons/acre). These systems arecommercially available for agricultural liquid applications of pestcontrol sprays and crop nutrient systems. All nozzles within theseexisting commercial systems pulse together at the same rate.

Such systems for dispensing agrochemicals as described above aredescribed, for instance, in U.S. Pat. No. 5,967,066 and in U.S. Pat. No.7,502,665, which are incorporated herein by reference. The systemsdescribed in the above patents include a liquid reservoir for containingan agrochemical placed in communication with a plurality of valvespositioned on a boom. In the '665 patent, a networked delivery system isdescribed that includes a communication network to establish operativecommunication between individual device nodes and a central operatorinterface. In the '665 patent, for instance, a plurality of vibrationsensors can be located adjacent to respective nozzles or valves thatindicate to the operator whether the valves are operating properly.

The systems described in the '066 patent and in the '665 patentrepresent great advances in the art. Although the systems described inthe above patents, however, suggest controlling the application rate ofthe agrochemical based on individual solenoid valves, variousimprovements in the art are still needed.

In particular, a need currently exists for an improved system and methodfor controlling individual valves or groups of valves for varyingapplication rates. A need also particularly exists for such a controlsystem that is capable of being retrofitted onto existing systems.

SUMMARY

The present disclosure is generally directed to an improved system andmethod for dispensing controlled amounts of a liquid agriculturalproduct through a plurality of valves that are individually controlledor controlled in groups. In this manner, when the valves are spreadacross a boom, application rates can be varied across the width of thesystem in response to one or more conditions or parameters that mayexist in the field. In one embodiment, for instance, the system can bedesigned so as to increase or decrease individual valve rates whilecontrolling the overall rate at which the liquid agricultural product isapplied to the field.

In one embodiment, for instance, the present disclosure is directed to asystem for applying liquid agricultural products to a field. The systemincludes a plurality of individually controlled valves, such as pulsewidth modulated valves. The valves can be in communication with a nozzleor any other dispensing device that either sprays the agriculturalproduct onto the field or injects the agricultural product into thesoil. As used herein, a “liquid agricultural product” includessolutions, emulsions, dispersions, suspensions, and the like. Theplurality of individually controlled valves are configured to emit theliquid agricultural product at a rate of volume per time.

The system further includes a controller in communication with each ofthe valves. The controller is configured to receive multiple flowrelated individual control values for each valve. The flow relatedindividual control values can be operator inputted into the system orcan be directly inputted into the system from a separate device, such asa sensor or a global positioning system. Each individual control valuefor each valve can be based upon a condition or parameter existingduring application. In accordance with the present disclosure, themultiple individual control values can be multiplied together to createa multiplied value for each valve. The multiplied value can then bedivided by an average of all the multiplied values to create a flowfactor for each valve. The controller is configured to control the rateat which the liquid agricultural product is emitted from each valvebased upon the calculated flow factor for each valve.

For example, in one embodiment, the rate that the liquid agriculturalproduct is emitted from each valve can be based upon a duty cyclepercentage that is controlled by the controller. The controller can beconfigured to receive a corporate duty cycle based upon an overalldesired application rate of the liquid agricultural product. In order tocontrol the individual valves, the controller can then be configured tomultiply the flow factor for each valve by the corporate duty cyclepercentage for calculating the duty cycle percentage for each individualvalve.

In one particular embodiment, the plurality of valves can be designed toemit an overall application rate of the liquid agricultural productbased upon volume of the product per area of land. The controller can beconfigured to vary the rate at which the liquid agricultural product isemitted from each valve based upon changing flow factors withoutchanging the overall application rate of the agricultural product.

The controller, which may comprise any suitable programmable device suchas a computer, may be configured to receive from several to many flowrelated individual control values. The flow related individual controlvalues generally comprise unitless values that are related to aparticular parameter or condition and are based upon the amount of theliquid agricultural product that is emitted by each valve. For a certaincondition or parameter, the flow related individual control values fromvalve to valve are also proportional to each other.

Many different types of flow related individual control values can beinputted into the system either automatically or by an operator. One ofthe flow related individual control values, for instance, may comprise avalve turn radius that comprises a value based upon a speed of eachvalve while the valve is traversing along an arc of a turn. Forinstance, the valves can be spaced apart along a boom. When a vehiclecarrying the boom makes a turn, certain valves will accelerate, whileother valves will decelerate or even stop depending upon the radius ofthe turn. Each valve can be given a flow related control value basedupon its position on the boom during the turn. This control value canthen be used by the controller to either increase or decrease the amountof product being dispensed by the valve.

Other flow related individual control values can be based upon irregularvalve spacing along the boom or may relate to swath overlap in order toavoid overapplying the agricultural product in certain areas. Swathoverlap, for instance, may be predicted or determined from inputreceived from the global positioning system. Swath overlap may also bebased upon the vehicle's speed, turn radius, antennae offset, and thelike. In one embodiment, for instance, a global positioning system maybe used in conjunction with an electronic compass to determine swathoverlap. The electronic compass, for instance, may be used to determineforward and backward orientation of the valves so as to accuratelydetermine valve location for use in overlap determination.

In one particular embodiment, swath overlap may be determined by lookingahead along each predicted valve position, to the right of eachpredicted valve position, to the left of each predicted valve positionand behind each predicted valve position according to a previouslydetermined safety-margin distance for areas previously applied with theagricultural product. The system can be configured to turn the valves onor off depending on their predicted position relative to the previouslyapplied areas based upon the safety-margin distance. The safety-margindistance can be operator controlled so as to prevent any overlap, or tocreate a controlled amount of overlap.

Many other flow related individual control values can also be inputtedinto the system. The flow control values, for instance, may relate to avehicle affect. For instance, increased or decreased application ratesfor a particular valve may be needed due to wheel tracks, dustgeneration, air disturbance, or any other condition caused by thevehicle. In another embodiment, one or more of the flow relatedindividual control values may be based on a field condition. Forinstance, application rates for certain valves may be increased ordecreased due to the presence of fence rows, access roads, certainterrain features, previous land usages, and the like that may exist onthe field being treated.

In still another embodiment, one or more of the flow related individualcontrol values can be based upon a vegetative affect. For instance, oneor more individual valves may be controlled by increasing or decreasingapplication rates due to a crop or weed density, a crop or weed health,a crop or weed species, a crop or weed sex, or the like.

As described above, the controller calculates a duty cycle percentagefor each valve. In one embodiment, if any of the flow related individualcontrol values for a valve are zero, then the controller can beconfigured to close the valve to prevent any agricultural product frombeing dispensed. In addition, the controller can be programmed with apre-set minimum calculated duty cycle percentage. In this manner, shouldthe calculated duty cycle percentage for any particular valve be greaterthan zero but less than the pre-set minimum, then the controller can beconfigured to assign to the valve the pre-set minimum based upon valvespecifications and performance.

The controller can be configured to recalculate the flow factor for eachvalve multiple times during application of the liquid agriculturalproduct. For instance, in one embodiment, the flow factor for each valvecan be calculated at least once a second, such as at least five times asecond, such as at least about 10 times a second.

In addition, the controller can be configured to determine valveposition which can assist in inputting the flow related individualcontrol values. For example, in one embodiment, the controller mayinclude a subroutine that assigns physical locations to each valve basedupon various inputs, such as valve spacing information that may beinputted by the operator.

In one embodiment, the controller can comprise a central hub wherein allthe valves and inputs for the multiple flow related individual controlvalues can be in direct electrical communication with the controller. Inthis manner, the electrical connections for the inputs and for thevalves are “spokes” that are connected to the central hub. By having thecontroller be configured as the central hub, the controller can includebattery power and a ground that can be shared by all system components.In one embodiment, the controller can operate at a Baud rate of lessthan about 150,000 Bd.

The controller can also include a graphic display that allows anoperator to input flow related individual control values. The graphicdisplay can also include various features. For instance, in oneembodiment, the graphic display can be configured to graphicallyillustrate each valve and the rate at which the liquid agriculturalproduct is being emitted from the valve.

The controller can also include a bypass system that bypasses allcontrols and operates any of the valves at a pre-set rate should anerror be detected that is related to the valve.

As described above, the rate at which the agricultural product isdispensed from the valves is based upon a duty cycle percentage that iscalculated by the controller. In some embodiments, it may be desirableto dispense the agricultural product from a valve at a particular pointin time at a rate that is greater than the maximum flow capacity of thevalve. Thus, in one embodiment, at least some of the valves may be usedin conjunction with a non-pulsating valve to increase rates whendesired. The non-pulsating valves can also be controlled by thecontroller.

Other features and aspects of the present disclosure are discussed ingreater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including thebest mode thereof to one skilled in the art, is set forth moreparticularly in the remainder of the specification, including referenceto the accompanying figures, in which:

FIG. 1 is one embodiment of a flow diagram of a calculation map forcalculating duty cycle percentages for valves controlled in accordancewith the present disclosure;

FIG. 2 is one embodiment of a flow chart for calculating a manipulatedflow signal when the system of the present disclosure is beingretrofitted to a preexisting system;

FIG. 3 is one embodiment of a flow diagram for calculating the overallrate at which the liquid agricultural product is being dispensed;

FIG. 4 is one embodiment of a flow chart and schematic diagram of asystem made in accordance with the present disclosure;

FIG. 5 is a plan view of one embodiment of an operator interface inaccordance with the present disclosure;

FIG. 6 is a plan view of one embodiment of a display screen that can beused with the operator interface illustrated in FIG. 5;

FIG. 7 is a plan view of one embodiment of an interactive display thatmay be produced by the operator interface illustrated in FIG. 5;

FIG. 8 is a plan view of one embodiment of an interactive display thatmay be produced by the operator interface illustrated in FIG. 5;

FIG. 9 is a plan view of one embodiment of an interactive display thatmay be produced by the operator interface illustrated in FIG. 5;

FIG. 10 is a plan view of one embodiment of an interactive display thatmay be produced by the operator interface illustrated in FIG. 5;

FIG. 11 is a perspective view of an embodiment of a system fordispensing an agricultural product in accordance with the presentdisclosure;

FIG. 12 is a perspective view of a valve assembly that may be used inthe system of the present disclosure;

FIGS. 13 a and 13 b are perspective views of opposing sides of a circuitboard that may be used in the valve assembly illustrated in FIG. 12.

Repeat use of reference characters in the present specification anddrawings is intended to represent the same or analogous features orelements of the present invention.

DETAILED DESCRIPTION

It is to be understood by one of ordinary skill in the art that thepresent discussion is a description of exemplary embodiments only, andis not intended as limiting the broader aspects of the presentdisclosure.

The present disclosure is generally directed to a method and system fordispensing agricultural products from a plurality of valves. In oneembodiment, the valves may comprise pulse width modulated valves. Inaccordance with the present disclosure, the system includes a controllerthat can control the valves individually based on input regarding anydesired condition or parameter that may exist during application.

Thus, in one embodiment, the method and system of the present disclosurecontrols the individual actuated valves to varying rates. The overallaverage of individual valves or nozzle rates can be controlled toaccommodate the independent flow and pressure objectives as desired. Theindividual valve rates, can be controlled to distribute more or lessflow to sub-sections of the nozzle or valve group. Generally, for everyvalve that is high flowing there is another valve that is low flowing.In this manner, existing commercially available rate control equipmentmay continue to be used while being retrofitted with the system andmethod of the present disclosure, to provide the further benefit offiner control resolution. Since the on/off pulse ratio of each valvehighly predicts the relative flow from each valve or nozzle, a controlsignal can be used without any feedback nor calibration to provideaccurate distribution schemes within the overall global controlparameters provided by these existing commercially available flow andpressure control systems.

Any input that is flow related may be used to distribute flow across aboom where the valves or nozzles are located. One such input that iseasily understood is turn radius compensation. While turning, theoutside nozzles on the boom travel much faster than the inside nozzles.The overall average of all nozzles will remain equivalent to the averagevehicle speed as in existing systems, however the on/off pulse signalcan be distributed to the nozzles across the boom according to thetravel speed of each nozzle.

The distributed on/off signal or flow related individual control valvescan come from external controllers as well. For instance, if multiplesensors are used across the boom to determine the rate of productrequired for a given job, the average can be sent to the commerciallyavailable systems for a single overall rate. The invention can then beemployed to distribute the flow to each nozzle according to the sensorreading from each of the multiple sensors. In effect yielding finerapplication rate resolution without interrupting the existing overallrate control system.

The sensor or sensors that can provide information to the controller canvary depending upon various factors and the particular application. Forinstance, any suitable sensor capable of sensing a parameter orcondition during application may be used. Such sensors can include speeddetection devices, temperature sensors, vibration sensors, vegetativecolor sensors, soil electrical conductivity sensors, infrared soilorganic matter sensors, moisture sensors, and the like.

This flow distribution can also come from a commercially available flowcontroller or otherwise which is preprogrammed with GPS maps that maywant varying application rates for any number of predetermined reasons.

Since each pulsing valve also acts as a shutoff valve, the system canturn on or off individual valves or nozzles for any number of reasons.Using a GPS map, the position of each valve can be recorded as anapplication job is accomplished. As the valves cross an already appliedportion of the field they can be turned off. Since the on/off pulsesignal highly predicts the flow from the valve or nozzle, these overlapvalves can be turned off and the commercially available rate controldevice manipulated to provide an accurate rate over a reduced swathwidth.

Overlap determination techniques are well documented in the prior art.However, the system of the present disclosure enables further control ofindividual flow distribution in a retrofit manner. Techniques aredescribed below that allow for retrofit manipulation of a commerciallyavailable rate controller without interruption of the global control offlow and pressure.

The term “select” is used to describe user configured flow distributionsfor such benefits as extra rate on fence rows (to control weeds, etc.),extra rates over wheel tracks, extra rates on male vs. female plantrows, etc., where the rate distribution is constant within a boom swath.

A graphical user interface can be used to accommodate the large amountof data associated with the set-up, control, and monitoring of thesystem. At a glance the operator can see the flow relationship of eachnozzle or valve and the total flow of the boom with respect to themaximum and minimum limits of the flow control system. The userinterface offers buttons and menus to facilitate the input of data suchas nozzle location, etc. Each automatic function of the controller isable to be disabled and run in manual mode, useful for troubleshootingand limping home after a component failure.

A system for power distribution to each nozzle or valve and a controlcomponent can be included to maximize current efficiency while beingsimple to install and manage. This “star” type configuration departsfrom traditional CAN bus techniques. Furthermore, the CAN system Baudrate can be reduced to increase reliability and extend physical lengthcapabilities required for modern application equipment commonly 150 feetin swath.

The system and method of the present disclosure can be incorporated intovarious different systems. For instance, the system and method of thepresent disclosure can be used in conjunction with any of the systemsand/or equipment disclosed in U.S. Pat. No. 7,311,044; U.S. Pat. No.7,162,961; U.S. Pat. No. 5,967,066; U.S. Pat. No. 5,704,546; U.S. Pat.No. 5,653,389; U.S. Pat. No. 5,134,961; U.S. Pat. No. 7,398,137; U.S.Pat. No. 7,383,114; U.S. Pat. No. 7,184,859; U.S. Pat. No. 7,103,451;U.S. Pat. No. 7,079,981; U.S. Pat. No. 7,054,731; U.S. Pat. No.6,928,339; U.S. Pat. No. 6,887,675; U.S. Pat. No. 6,813,544; U.S. Pat.No. 6,810,315; U.S. Pat. No. 5,919,242; U.S. Pat. No. 6,522,948; U.S.Pat. No. 4,630,773; U.S. Pat. No. 6,941,225; U.S. Patent ApplicationPublication No. 2006/0273189; and U.S. Patent Application PublicationNo. 2008/0086249, which are all incorporated herein by reference.

Referring to FIG. 11, one embodiment of a system for dispensing anagricultural product in accordance with the present disclosure is shown.The system 100 includes a tractor 120 to which a spray boom 140 ismounted for treating agricultural fields with a liquid agriculturalproduct. In the embodiment illustrated, the agricultural product isdispensed as a spray S onto the field. It should be understood, however,that in other embodiments, the agricultural product may be injected intothe soil as the tractor 120 traverses the field.

The tractor 120 includes an engine 200 and tires or wheels 220 toprovide locomotion and a cab 240 in which an operator operates thesystem. The system includes a product reservoir 250, which is mounted onthe tractor 120. The product reservoir 250 is in liquid communicationwith the boom 140. As shown, the boom 140 may include a left boomsection 142 and a right boom section 144. A manifold 146 may run alongthe left boom section and the right boom section. The boom sections may,in one embodiment, correspond to soft booms, which are set up using aprogrammable map loaded into a controller as will be described ingreater detail below. Further, the system may include more than two boomsections in which the valves in those sections are controlled as a groupor individually.

As shown in FIGS. 11 and 12, a plurality of valve assemblies 160 arespaced apart from each other on the manifold 146 for dispensing theagricultural product. Referring to FIG. 12, a valve assembly 160 isshown in more detail. The valve assembly 160 includes the valve 260which can be coupled to any suitable device adapted to dispense theagricultural product. For example, in one embodiment, the valve 260 canbe coupled to a nozzle for spraying a liquid product onto a field. In analternative embodiment, the valve 260 may be coupled to an injector forinjecting an agricultural product into the soil.

In one embodiment, the valve assembly 160 can include a module 300. Inthe embodiment shown, the module 300 is attached to the valve assembly160. In an alternative embodiment, however, the module 300 can be moredirectly incorporated into the valve assembly.

The valve assembly 160 is in fluid communication with the manifold 146for receiving the agricultural product from the liquid reservoir.

In one embodiment, the valve 260 may comprise a pulse width modulatedvalve. Such valves, for instance, are described in U.S. Pat. No.5,967,066. Such valves can provide various advantages and benefits. Forexample, pulse width modulated valves are not only well suited todispensing the agricultural product in controlled amounts, but can do sowithout significantly decreasing the pressure within the distributionmanifold. Thus, when dispensing volatile liquids, such as ammonia, thevalves can sustain back pressure and prevent vaporization.

As shown in FIG. 12, the valve 260 is in communication with an actuator246. The actuator 246 pulsates between an open position and a closedposition according to a duty cycle percentage. For instance, in oneembodiment, the valve is controlled by an electrically actuatedsolenoid. In other embodiments, however, the valve may be pneumaticallyor hydraulically actuated. The term duty cycle percentage of thepulsating valve is defined as the percentage of time the valve is opendivided by the total operation time. The duty cycle controls the flowrate of the fertilizer through the dispensing tubes in a rapid on/offmanner. Such valves can also control various other parameters, such asdroplet size, spray pattern, etc.

In the embodiment illustrated, the module 300 is used to connect thesolenoid actuator to a controller for controlling the duty cyclepercentage of the valve or other functions. As explained above, in oneembodiment, the module can be a part of the solenoid actuator for directconnection to a controller. In the embodiment illustrated, however, themodule includes an alarm, such as a visual alarm 244. In the embodimentillustrated, the alarm 244 comprises an LED. The LED is used to conveyvarious information to the operator. For example, in one embodiment, theLED may indicate that the valve assembly has been registered by thecontroller and/or to indicate a problem associated with the particularvalve.

Referring to FIGS. 13 a and 13 b, in one embodiment, the control of thevalve actuator can be done through a circuit board 132. The circuitboard 132 can also be used to monitor the valve or nozzle. In oneembodiment, the valve assembly can have an operational frequency rangeof from about 0 to about 15 Hz and can have a duty cycle range of from0% to 100%. The circuit board 132 can include an analog circuit boardside 134 a and a digital circuit board side 134 b. The analog side 134a, for instance, may include an accelerometer 136 with an amplificationand filtering circuit for monitoring nozzle variation. The digital side134 b, on the other hand, can include a bus interface 148 and amicrocontroller 138.

In addition to the above, the dispensing system 100 as shown in FIG. 11can include various other components and devices. For instance, in oneembodiment, the system 100 can include a flow meter placed between theliquid reservoir 250 and the distribution manifold. The flow meter canbe used to monitor and/or control the amount of liquid agriculturalproduct that is fed to the manifold. In one embodiment, the flow metercan send flow rate information to a controller for use in calculatingduty cycle percentages in relation to the speed at which the valves arebeing traversed across the field.

Optionally, the system can also include a pressure regulator. Thepressure regulator can be, for instance, a throttle valve that can beused for regulating the pressure of the liquid agricultural productwithin the system.

The particular liquid agricultural product that is dispensed through thesystem 100 as shown in FIG. 11 may vary dramatically depending upon theparticular application and the desired results. The liquid agriculturalproduct, for instance, may comprise a spray that is intended to comeinto contact with a crop, pest or soil. Each valve assembly can includea spray tip or nozzle to create and distribute spray droplets that carrythe active ingredient within the spray to the target crop, pest or soil.In one embodiment, for instance, the liquid agricultural product maycomprise a liquid fertilizer. The liquid fertilizer can be dispensedthrough any suitable soil engaging device such as a knife, coulter, orstream injector that carries the liquid fertilizer to the soil. In oneparticular embodiment, for instance, the liquid fertilizer may comprisea volatile liquid, such as anhydrous ammonia that is preprocessed bycooling or pressurization into a liquid state.

In an alternative embodiment, the liquid agricultural product maycomprise irrigation water that may contain nutrients or chemicals. Instill another embodiment, the liquid agricultural product may comprise acontrol agent, such as a pest control agent or a weed control agent.

As described above, the use of pulse width modulated valves can help tomaintain pressure and can be used to establish spray droplet size. Inone embodiment, the spray droplet size can be specific to a particularvalve or nozzle in order to reduce the amount of target drift or toenhance the spray coverage in a specific area. Nozzle or valve pressurecan also be used to establish the velocity of the application stream ata specific site to control the amount of splash, or to control the depthof penetration into the soil, which is especially useful when injectingnutrients behind rolling coulters.

In accordance with the present disclosure, the system further includesvarious controls that can be sold as a stand alone system or can beeasily retrofitted onto existing systems. In particular, the sum of theindividual valve flows is controlled to achieve corporate flow andpressure objectives while the individual flow of each nozzle iscontrolled to achieve a specific flow distribution according to theproduct of multiple flow related steady state or variable objectives.More particularly, the system can include a controller capable ofreceiving various inputs. The inputs may comprise multiple flow relatedindividual nozzle or valve control requirements or values for thevalves. The flow related individual control values for the valvescomprise unitless values that are proportional to each other and can bebased upon any suitable parameter or condition regarding the applicationof the liquid agricultural product. The flow related individual controlvalues, for instance, can be inputted into the controller by a user oroperator or can be automatically inputted into the controller from aseparate component or electronic device, such as a sensor or a globalpositioning system.

In accordance with the present disclosure, the controller is configuredto multiply together the flow related individual control values for eachvalve. Each individual unitless value is then divided by the average ofall individual valve or nozzle unitless values to create a flow factorfor each valve or nozzle. The flow factor for each valve or nozzle canthen be multiplied by a corporate pulse width modulation duty cyclepercentage to achieve an unequal distribution of individual nozzle orvalve flows that together meet the traditional corporate flow andpressure objectives.

Referring to FIG. 1, for instance, a flow chart and calculation map thatillustrates various inputs that can be received by a controller inaccordance with the present disclosure is shown. In addition, variouscalculations that can be performed by the controller in order toindividually control each of the nozzles in the system are illustrated.As shown, the top row of numbers 1 represents each of the valves ornozzles contained within the system. For exemplary purposes only, inthis embodiment, the calculation map indicates that up to 256 valves ornozzles can be identified in the system. Character numerals 2 through 7,on the other hand, identify various flow related individual controlvalues that can be inputted for each of the individual valves. In thisembodiment, for instance, the individual control values shown beinginputted into the system include an auxiliary flow scalar value 2 foreach valve, a select flow scalar value 3, a manual boom shutoff value 4,a turn radius scalar value 5, a turn backup shutoff value 6, and anozzle or valve overlap shutoff value 7.

As described above, the system of the present disclosure is particularlywell suited for being retrofitted with existing systems. In thecalculation map illustrated in FIG. 1, the first three flow relatedindividual control values 2, 3, and 4 for the valves represent valuesthat are to be inputted to the system from a preexisting controller. Theauxiliary value 2, for instance, may comprise a value inputted into thesystem from an external controller. The select value 3 and the manualshutoff value 4, on the other hand, may comprise operator inputtedvalues that may be available on existing systems.

Flow related individual control values 5, 6 and 7, on the other hand,represent further controls that can be incorporated into the system ofthe present disclosure for more precise application based upon varioussystem conditions and parameters. The turn ratio value 5, for instance,may comprise control values for each valve depending upon the velocityof the valve during a turn radius. The turn backup shutoff value 6, onthe other hand, may be used to shutoff valves when it is sensed that thevalves are moving backwards during application. The overlap shutoffvalue, on the other hand, may comprise a value for each of the valvesdepending upon a sensed overlap in application on the field.

Although the embodiment illustrated in FIG. 1 includes seven inputs forvarious flow related individual control values, it should be understoodthat the system may include more or less inputs for various othervalues. For instance, in one embodiment, the system can be designed toreceive over ten individual control values for each valve, such as fromabout 10 to about 30.

As described above, the flow related individual control values areunitless values inputted into the system that are used to control theindividual valves based upon a particular condition or parameter. In oneembodiment, for instance, the individual control values can vary fromabout 0.1 to about 10. In this embodiment, a value of “1” would indicatethat the valve during that particular condition or parameter is tooperate according to a corporate duty cycle percentage. Based upon theparameter or condition, the control value can be increased or decreasedfor any given valve. Increasing the control value, for instance,indicates that the particular valve is to increase in flow rateaccording to a particular condition or parameter. An individual controlvalue less than 1, on the other hand, translates into a decreased flowrate regarding the particular condition.

Although the individual control values are unitless, all of the valuesare proportional to each other for a particular condition or parameter.More specifically, the values are proportional to each other withrespect to the amount or rate at which the liquid agricultural productis dispensed from each of the valves.

In some circumstances or conditions, it may also be desirable totemporarily or permanently shut off a particular valve duringapplication. For instance, as shown in FIG. 1, it may be desirable toshut off a valve if it is indicated that the valve is moving backwardsover a portion of the field where the agricultural product has alreadybeen applied. Similarly, it may be desirable to shut off a valve whenthe valve is moving forward but yet an overlap in application isdetected. In order to cause a valve to shut off in accordance with thepresent disclosure, a “zero” is inserted into one of the individualcontrol values. As will be made clear from a description of thecalculations, inserting a zero into any of the control values will causea valve to shut off at least temporarily until the zero value isreplaced with a value greater than zero.

For instance, as shown in FIG. 1, once all of the multiple flow relatedindividual control values are inputted into the system, the values aremultiplied together for each valve. This multiplied value is inserted inrow 9. As also shown, these values are then added together to create asum of actual values 9. The controller can also be configured to countthe number of actual values 10 which indicates the number of valves thatare operating. By dividing the sum of actual values 9 by the count ofactual values 10, an average control value is calculated for all of thevalves.

As shown in FIG. 1, the multiplied value of the individual controlvalues for each valve is then multiplied by the count of actual values10 and then divided by the sum of actual values 9. In other words, themultiplied value for each valve is divided by the average control valuefor all the valves. This resulting number represents a flow factor foreach valve. The flow factor can then be used to control each individualvalve depending upon all the parameters and conditions that have beeninputted into the system.

In one embodiment, for instance, a nominal or corporate system dutycycle percentage 13 can be inputted into the controller. The flow factorfor each valve can then be multiplied by the corporate duty cyclepercentage to arrive at a normalized duty cycle percentage 12. Thenormalized duty cycle percentage 12, in one embodiment, can then becompared to a pre-set minimum duty cycle percentage and/or pre-setmaximum duty cycle percentage that may be inputted into the controller.For instance, in one embodiment, the system may be configured such thatif a particular valve is to be on, that the duty cycle percentage notfall below a certain value, such as for instance 10%. Thus, if thenormalized duty cycle percentage 12 is calculated to be less than 10%,the controller may be configured to automatically readjust the number tothe minimum duty cycle percentage. This provides the actual orconditioned individual pulse duty cycle percentage 14 as shown inFIG. 1. The duty cycle percentage 14 as determined by the controller isthen used by the controller to control the solenoids of each of theindividual valves for dispensing agricultural product according to adesired amount. As described above, if any of the individual controlvalues for any of the valves are zero, the pulse duty cycle percentage14 as shown in FIG. 1 results in a zero which closes the valve entirely.

Through the above inputs and calculations, each valve in the system canbe precisely controlled based upon multiple conditions and parametersthat exist during application. Of particular advantage, the controlvalues are all proportional to each other and when calculated accordingto the calculation map results in a single multiplied value that createsa proportional flow factor for interaction with a corporate duty cycle.Thus, in one embodiment, each of the valves or nozzles can beindividually controlled regarding the rate at which the agriculturalproduct is dispensed without changing the overall amount of product thatis applied to the field. Further, as shown in FIG. 1, the system isparticularly well suited to be retrofitted on existing systems that mayonly include a few controls for the valves.

As described above, various different flow related individual controlvalues can be inputted into the system in accordance with the presentdisclosure. As an example, for instance, FIG. 1 includes a turn ratiovalue 5. This value, for instance, is one for each valve when the valvesare all moving in a forward direction. When the vehicle or tractorundergoes a turn radius, however, the turn ratio values 5 change for thedifferent valves depending upon the actual speed of the valves duringthe turn. For instance, individual nozzle or valve flow may becontrolled for the actual speed that the valve or nozzle is traversingalong the arc of the turn. In some instances, for instance, one or moreof the valves may be traveling backwards during a turn. In accordancewith the present disclosure, a value of zero can be assigned to thevalve during the backwards movement in effect shutting the valve ornozzle to prevent an overlap in application. If the valve, however,increases in speed during the arc of the turn, the turn ratio value forthat particular valve may be greater than one. For a valve thatdecreases in speed during the arc of the turn, on the other hand, theturn ratio value for that valve may be less than one. These types ofvalues can be assigned to each of the valves depending upon otherconditions and parameters.

In addition to a turn ratio value 5 as explained above, various othermultiple flow related individual control values will now be described.It should be understood, however, that the following description is notexhaustive of the various values that can be incorporated into thesystem.

Other multiple flow related individual control values can include, forinstance, irregular valve or nozzle spacing on the boom. In oneembodiment, the multiple flow related individual control values may berelated to a vehicle affect. For instance, increased or decreasedapplication rates with respect to a particular valve may be needed dueto wheel tracks caused by the vehicle, dust generation caused by thesystem, air disturbance caused by the system, and the like. Wheel trackscaused by a vehicle, for instance, may require greater amounts of a weedcontrol agent. In particular, it has been discovered that weeds becomemore resilient where wheel tracks are located. Thus, when dispensing aweed control agent, it may be desirable to dispense greater amounts ofthe agent where the wheel tracks are located. In this regard, anindividual control value for the wheel tracks can be inputted into thesystem based upon the valves that are located over where the tracks areformed.

In another embodiment, flow related individual control values can beinputted into the system that are related to one or more field affects.Field affects may require increased or decreased application rates dueto the presence of fence rows, access roads, terrain, previous landusages, and the like. The presence of fence rows within a field, forinstance, may promote the growth of a greater density of weeds. Thus, itmay be desirable to apply greater amounts of a weed control agent alonga fence row. In accordance with the present disclosure, this informationcan be manually inputted into the system or can be automaticallyinputted into the system. When automatically inputted into the system,for instance, a global positioning system may identify the presence of afence row and modify the values of the valves located along the fencerow accordingly.

In still another embodiment, one or more of the multiple flow relatedindividual control values may relate to a vegetative affect. Forinstance, increased or decreased application rates from various nozzlesor valves may be desired due to crop or weed density, crop or weedhealth, crop or weed species, crop or weed sex, or the like.

In still another embodiment, various multiple flow related individualcontrol values may be inputted into the system based upon a globalinformation system (GIS) rate prescription map, a field boundary map, orthe like. A rate prescription map or a field boundary map, for instance,may be used to pre-set the valves for dispensing amounts of theagricultural product based upon the dimensions of the field or due tovarious geographical objects that may be present in the field. Rateprescription maps and field boundary maps, for instance, exist onpreexisting commercial processes. Thus, these values may comprise theauxiliary values 2 as shown in FIG. 1.

In one embodiment, the system can include various sensors positionedalong the boom that can input flow related individual control valuesinto the controller. The sensors may include, for instance, vegetativecolor sensors, soil electrical conductivity sensors, infrared soilorganic matter sensors, moisture sensors, and the like. Sensors may alsobe used to sense soil fertility and nozzle or valve pressure.

In still another embodiment, one of the multiple flow related individualcontrol values may comprise a swath overlap value. For instance, if anarea or part of the field is traversed that is known to have alreadybeen treated with the agricultural product, various individual valves ornozzles in the overlap area may be controlled to prevent overapplicationof the agricultural product. The affected valves, for instance, can havea reduced flow rate or can be shut off in the overlap area. The presenceof an overlap area can be predicted or determined using variousdifferent techniques and methods. For instance, the overlap system canbe predicted or determined from GPS resolution, vehicle speed, turnradius, antennae offset, and the like. In one particular embodiment, forinstance, a constant-curvature, constant-acceleration algorithm may beused to predict position while traversing between GPS coordinates. In analternative embodiment, an accelerometer may be used in addition to GPSdata to determine the forward/backward orientation of the vehicle suchthat the nozzle or valve location is accurately determined for use inoverlap determination. In still another embodiment, a simple first-orderdynamic model that uses machine geometry may be used to predict nozzleor valve position.

In still another embodiment, an electronic compass may be used inaddition to GPS data to determine the forward/backward orientation ofthe vehicle such that nozzle or valve location is accurately determinedfor use in overlap determination.

In one embodiment, overlap calculations can be compared to an overlapsafety margin that may be fixed or inputted by an operator. Thesafety-margin distance, for instance, may comprise a distance where someoverlap is permitted. For instance, the safety-margin distance may varyin one application from 0 inches to about 36 inches. At 0 inches, thesystem will allow for no overlap. In other embodiments, however, thesafety-margin distance may be a positive number that allows for someoverlap in order to prevent skips or areas that remain untreated.

In one embodiment, the application overlap is determined by lookingahead along each predicted valve or nozzle position, to the right ofeach predicted valve or nozzle position, to the left of each predictedvalve or nozzle position and behind each predicted valve or nozzleposition according to a previously determined safety-margin distance forpreviously applied areas. The valves can be turned on or off dependingon their predicted position relative to the previously applied area sothat if the safety-margin distance calls for “no skips” then the valveshuts off inside the previously applied area by the safety-margindistance. If the safety-margin distance calls for “no overlaps”, thenthe nozzle or valve shuts off before entering the previously appliedarea by the safety-margin distance.

In one embodiment, the accuracy of the overlap system will be predictedor determined as described above from GPS resolution, vehicle speed,turn radius, antennae offset, etc. and compared to an inputted overlapsafety-margin expectation to sound an alarm and display a warningmessage that the overlap system is working within the expected accuracymargins or that the overlap system is outside of the expected accuracymargins such that the operator may adjust his expectations or disengagethe overlap system and change to another method of overlap control.

For instance, the system can include controls that may prevent falsedetermination of overlap. For example, false determination of overlapdue to close proximity of adjacent valves or nozzles may be avoided bytesting for adjacent nozzle overlap cases and ignoring those cases.False determination of application overlap due to small movement ofnozzles along the application path may also be avoided by delaying therecording of “applied” regions until the nozzle or valve has passedcompletely away from the region and only then storing the applied regioninformation.

The multiple flow related individual control values inputted into thesystem can change continuously as the valves traverse across the field.In this regard, the controller can continuously calculate flow factorsfor each valve during the process. In one embodiment, for instance, flowfactors for each valve can be calculated at least once per second, suchas from about 5 times to about 10 times per second.

Although pulse width modulated valves provide various advantages andbenefits as described above, many of these types of valves may havecapacity limitations. In some instances, it may be desirable to dispensegreater amounts of the agricultural product at certain locations thatare outside the capacity requirements of the pulse width modulatedvalves. In this regard, secondary valves can also be placed inconjunction with the pulsing valves to boost flow capacity.

In one particular embodiment, a non-pulsing solenoid valve may be usedin conjunction with a pulsing valve such that when the pulsing valve isat its maximum flow capacity, the non-pulsing valve may be turned on tosupplement the capacity of the pulsing valve. Furthermore, the systemupon activation of the non-pulsing valve, may reduce the pulse dutycycle percentage of the pulsing valve to a mathematically determinedduty cycle percentage equivalent to the maximum flow capacity of thepulsing valve. In this way, a seamless transition in flow results as thesupplemental non-pulsing valve is added to and subtracted from thesystem. In one embodiment, multiple non-pulsing valves may be used tosupplement the maximum flow capacity of a pulsing valve.

As described above, the system of the present disclosure can be easilyretrofitted onto an existing system. When retrofitted onto an existingsystem, it may be necessary to intercept and modify the flow feedbacksignal from the preexisting controller to correct the signal for flowchanges not considered in that preexisting controller's controlalgorithm. In effect, the preexisting rate controller will satisfy thetraditional corporate flow and pressure objectives but will be decoupledfrom local requirements being controlled by the method and system of thepresent disclosure.

One flow diagram for intercepting and modifying the flow signal from apreexisting flow sensor is shown in FIG. 2. As shown, the flow signalintercepted from the preexisting flow sensor 16 is multiplied by theratio of the sum of expected values 8 as shown in FIG. 1 to the sum ofactual values 9 as also shown in FIG. 1. This ratio allows forcorrection of the multiple flow rated individual control values inputtedinto the system and contained in the flow factor for each valve thatwere not previously considered by the preexisting device.

For instance, a flow change that may not be considered by a preexistingrate controller may comprise shutting off individual nozzles or valvesdue to nozzle overlap as detected using any of the methods describedabove. As individual nozzles or valves are shut off, the preexistingrate controller's flow feedback device's signal will be corrected as ifthe individual nozzle had not been shut off. Hence, the corporate flowobjectives will be met by the commercial rate controller while the localobjectives will be met by the system of the present disclosure. In thiscase, any as-applied mapping done by the preexisting rate controllerwill be in error, however, the true as-applied application will beaccurate.

Similarly, a flow change not considered by a preexisting rate controllermay also comprise activities such as individual nozzles or valves beingshut off when a tight turn radius is completed by a vehicle and wherecertain valves are traveling backwards as may be detected using GPSmethods. The controller of the present disclosure, however, can correctthe preexisting flow feedback device's signal so that the corporate flowobjectives are met by the preexisting rate controller while the localobjectives are met by the system of the present disclosure.

Once a valve or nozzle that has been turned off is reactivated, thecontroller of the present disclosure can activate the preexisting ratecontroller's remote inplement shutoff switch, causing the commercialrate controller to consider the application started again.

As shown in FIG. 3, the controller of the present disclosure can also beconfigured to calculate a flow value that may be transmitted to apreexisting rate controller in a retrofit system. For instance, thetotal flow from the system can be mathematically calculated according tothe sum of individual nozzle or valve flows as calculated from theindividual valve pulse duty cycle percentages, individual valve solenoidvalve orifice size, individual valve deposition orifice size, systempressure, and properties of the liquid being dispensed. This calculatedflow can then be transmitted to a preexisting controller for feedback tocontrol to the traditional corporate flow and pressure objectives.

As shown in FIG. 3, the calculated flow value 17, for instance, can becalculated by multiplying a flow constant for nozzle and product applied18 by the square root of inlet and outlet nozzle pressure 19 and furthermultiplied by the sum of pulse duty cycle percentages 11 as shown inFIG. 1.

Referring now to FIG. 4, one embodiment of a schematic diagram of asystem made in accordance with the present disclosure is shown. Asillustrated, in this embodiment, the controller can comprise a centralhub 20 that distributes power, routing signals and repeatingcommunications to all of the other components. As shown, the central hubor controller 20 is connected to an operator interface 21 which mayinclude a display screen and controls used by an operator. Thecontroller 20 is also connected to a gateway 22 for intercepting sensorsand actuators in communicating with external controllers as listed. Inthis embodiment, the system includes eight different valve controlmodules 23 that control individual nozzle or valve pulses. Theindividual valves or nozzles 24 are in communication with acorresponding valve control module. In the embodiment illustrated, asingle valve control module may be in communication with up to ninedifferent valves. If desired, a Y cable 25 may also be used to allow formultiple component connections on a single port.

The system as shown in FIG. 4 can also include a shutoff adapter 26 forintercepting boom section shutoff signals from rate controllers. Theshutoff adapter 26, for instance, can indicate when a group of valves ona particular section of the boom are shut off.

The controller 20 is further in communication with a pressure sensor 27and an ignition input 28 for turning on or off the system components viaa key switch. The system can further include a circuit breaker 29 forcurrent overload protection and various vehicle battery connections 30.

Having the controller 20 comprise a central hub in a “star design” mayprovide various advantages and benefits. As shown, power, CAN, analogand digital signals residing on individual circuits can be bundled intoa single standardized cable, with the cables being connected to thecentral hub controller 20. The configuration shown in FIG. 4 is incontrast to various standard designs of CAN systems where nodes areinterconnected in a “daisy-chain” fashion. The central hub configurationshown in FIG. 4, for instance, provides a more efficient distribution ofnon-CAN signals in conjunction with the CAN signals.

In addition, battery power and ground can be provided to each componentin the system via the central hub 20. Connections are thus minimizedmaximizing the efficiency of power distribution. This design isespecially beneficial when using a plurality of solenoid actuated valveswhich in some systems pose a large current load while individualsolenoid performance is significantly impacted by voltage. Further, theswitched ignition power 28 is provided to each component on the systemvia the central hub. Thus, a low current switched ignition voltage isused to power up and down each component on the system. This allows eachcomponent to possess its own high current battery power switcheliminating the need for a very large capacity battery power switch forthe whole system at the battery location, thus reducing cost and makingthe power distribution design more efficient. In addition, a terminatingresistor may be present within each component residing within thesystem. This eliminates the need for external terminating resistors andmakes all components similar in design.

In one embodiment, CAN communications are provided to each component onthe system via the central hub, where passive repeaters are used toaccurately synchronize and distribute the CAN messages to and from eachcomponent.

A digital turn-on signal may be provided to each solenoid actuated valvemodule to facilitate boom section control in a common manner. As will bedescribed in greater detail below, removing its functionality from theCAN allows for limp-home features greatly beneficial in agriculturalapplications where off-road and remote breakdowns are common and need tobe addressed.

As shown in FIG. 4, an analog pressure sensor signal can also betransmitted from the central hub to the node responsible for pressurecontrol. In the past, this functionality was typically placed with aCAN. Removing this functionality from the CAN reduces the number ofnodes within the system and allows for common sensors and fieldtroubleshooting techniques.

In order to assist in preventing communication errors, the CANcommunication rate or Baud rate can be relatively slow. For instance,the Baud rate may be slowed down from a standardized rate (of commonly250K) to a slower rate of less than about 150K Bd, such as at a rate ofabout 125K Bd. Slowing down the Baud rate facilitates longer cablelengths required on modern application equipment with swath widthsnearly 200 feet in length. This slower Baud rate increases therobustness of the communications and reduces the risk of communicationfailures in the field.

During operation, the controller 20 can include an input or beprogrammed with a memory map of the field to be treated. As will bedescribed below, the controller can also include a subroutine thatlocates the position of the valves or nozzles contained within thesystem. In accordance with the present disclosure, a 2-dimensional ringbuffer technique may be used to allocate data memory storage locationssuch that the as-applied nozzle or valve position memory map isself-centering in both X and Y directions.

Referring now to FIGS. 5-10, one embodiment of a user interface display21 that may be incorporated into the system of the present disclosure isshown including a graphic display 44. As shown in FIG. 5, in addition tothe graphic display 44, the operator interface 21 includes variousoperating lights and functions. For instance, the operator interface caninclude an Automatic/Manual Control Button and Indicator Light 31, anAlarm Enable/Disable Control Button and Indicator Light 32, a TurnCompensation Enable/Disable Control Button and Indicator Light 33, anOverlap Compensation Enable/Disable Control Button and Indicator Light34, a System Enable/Disable Control Button and Indicator Light 35, aCursor Navigation Control Buttons, Up/Down/Right/Left 36, an EnterControl Button 37, an Escape Control Button 38, a Touchpad Graphic Decal39, a Select Control Button and Indicator Light #4 40, a Select ControlButton and Indicator Light #3 41, a Select Control Button and IndicatorLight #2 42, a Select Control Button and Indicator Light #1 43, aLocation Set-Up Control Button and Indicator Light 45, a System Set-UpControl Button and Indicator Light 46, and a Select Set-Up ControlButton and Indicator Light 47.

With respect to the operator interface illustrated in FIG. 5, the selectcontrol buttons 40, 41, 42 and 43, in one embodiment, can bepreprogrammed to input multiple flow related individual control valuesfor the valves into the system based upon the existence of a particularcondition or parameter. For instance, in one embodiment, select controlbutton 42, for instance, may be preprogrammed with individual controlvalues for all the valves in the system in order to compensate for thepresence of vehicle wheel tracks and a fence row.

For instance, referring to FIG. 6, an operational mode screen isillustrated that includes a System Error Text Display Box 48, a SystemNominal Pulse Duty Cycle Numerical Display Box 49, an Arrow IndicatorGraphically Depicting #49 50, a System Pressure Graphical IndicatorDepicting #52 51, a System Pressure Numerical Display Box 52, aGraphical Display Grid Lines To Assist in Graphical Comparisons of Data53, a Valve Diagnostic Numerical Display Box 54, and a Nozzle iconGraphically Depicting Location and Pulse Duty Cycle Percentage of eachNozzle 55.

More particularly, the nozzle icon location 55 illustrates not only thelocation of each valve or nozzle in the system but also shows therelative amount of the agricultural product being dispensed by thenozzles. As shown, a group of nozzles on the left hand side of thescreen are emitting a greater flow rate than most of the remainingnozzles. Two groups of nozzles in the center of the screen are alsoemitting the agricultural product at a greater rate. The left hand sideof the screen may show nozzles positioned along a fence row, while themiddle groups of nozzles may show nozzles positioned over wheel trackswhere greater amounts of the agricultural product may be desired. Thus,the system of the present disclosure can be equipped with a graphicdisplay that allows an operator to check and make sure that the nozzlesare operating according to a pre-set condition.

Referring to FIG. 7, a select setup screen is shown that may be used toprogram in the multiple flow related individual control values thatresult in the actual application rates as shown in FIG. 6. In oneembodiment, for instance, each select setup screen may include anAuxiliary Boom Assignment Configuration Box 56, a Soft Boom AssignmentConfiguration Box 57, a Valve Test Assignment Configuration Box 58, aNozzle Icon Graphically Depicting Location and Pulse Duty CyclePercentage of Each Nozzle 59, a Graphical Display Grid Lines To Assistin Graphical Comparisons of Data 60, a Valve Size Data Entrance Box 61,a Nozzle Size Data Entrance Box 62, a Flow Scalar Value Data EntranceBox 63, and a Rank Value Data Entrance Box, Even/Odd/Open/Close 77.

In essence, the select set up screen as shown in FIG. 7 can be used tonot only input multiple flow related individual control values forparticular conditions or parameters, but can be used to preprogram theselect control buttons 40-43 as shown in FIG. 5.

In one embodiment, the controller included in the system of the presentdisclosure can include a graphical depiction of individual valves ornozzles. The controller can also be configured to identify the actualphysical locations of valves and nozzles. For instance, the controllermay include a subroutine that assigns physical location measurements toeach nozzle or valve to later be used in spacial calculations requiredto accurately dispense the agricultural product to the valves. In oneembodiment, for instance, the controller can be configured toautomatically assign physical locations to the valves based upon anoperator inputting a valve spacing. The graphical display can thendepict the individual valves as shown in FIGS. 6 and 7 which may then beused by the operator to identify the actual location of a single valveor a subset of valves. A valve or set of valves may need to beidentified by the operator in order to input flow related individualcontrol values. Alternatively, the actual location of a valve or a setof valves may be helpful where errors are detected by a diagnosticprogramming within the system. In this manner, the operator canefficiently inspect and service the specific valve or valvesexperiencing errors.

Referring to FIG. 8, a location setup screen that may be incorporatedinto the controller and that appears on the graphic display is shown.The location setup screen can include a VCM Serial Number Indicator Box64, a VCM Identification Number Indicator Box 65, a VCM NozzleIdentification Indicator Box 66, a Location Indicator and Data EntranceBox 67, a Nozzle Element Number Indicator Box 68, and a Valve TestAssignment Configuration Box 69.

In the embodiment illustrated, the nozzle location is defined by thedistance the nozzle is located from a center line extendingperpendicular to the boom. A positive number, for instance, may indicatea valve positioned right of center, while a negative number may indicatethe position of a valve left of center.

Referring to FIG. 9, an auto location setup screen is shown. Theautomatic location setup screen includes a Graphical Reference Depictionof Application Machine 70, a VCM Graphic of VCM being Configured 71, anda Graphic(s) of All VCMs in System Showing Position and Orientation ofeach VCM 72. The screen illustrated in FIG. 9 can be the screen shownduring automatic positioning of the valve by the controller.

Referring to FIG. 10, a system setup screen is also shown that shows thevarious inputs that have been received by the controller regarding astandard menu. In this embodiment, the system setup screen includes aSet-Up Item Identification Number 73, a Set-Up Item Description 74, aYellow Cursor Indicating Set-Up Item Being Selected and Configured 75,and a Set-Up Value 76.

As shown above, the graphical electronic display may be used to operateand set up the system such that a large amount of data required tooperate the system is reduced to graphical elements that are easy forthe operator to understand. In one embodiment, each valve or nozzle canbe represented graphically by an icon placed spacially on the displayscreen horizontally according to each actual physical position on theapplication implement. This icon is placed spacially on the displayscreen vertically according to its actual pulse duty cycle percentage.The resulting graphical illustration shows individual nozzle performanceas well as the performance of the plurality as a whole. The graphicaldepiction of individual nozzles and the plurality of nozzles is used todisplay the current operating conditions of the application device inreal time. In addition, the graphical depiction of individual valves andthe plurality of valves can be used to display user defined flowparameters to be saved in memory and later recalled for operation. Thisspecific graphical depiction can be further used to identify and selectthe desired set of flow parameters from multiple saved sets of flowparameters.

In addition to the above, the controller and graphic display can beprogrammed with various other features and components. For instance, inone embodiment, the controller can be configured to automatically detectthe available valves and to assign default setup data to the valves sothat the system is fully operational, even without receiving any flowrelated individual control values for any of the valves. In thisembodiment, a message may be displayed to the operator that the systemis operating under default parameters and that application errors mayoccur if the system is not uniquely configured for the specificapplication at hand. In one embodiment, the operator may be required topush a button to continue, acknowledging that he is aware of the defaultoperating parameters and the potential errors. The default system canprovide for easy use of the system and may allow the system to beinstalled and tested in a generic environment where the finalconfiguration of the valves may not be readily known.

The system can also include various emergency bypass features shouldsystem errors occur in the field. The bypass features, for instance, mayallow the system to continue dispensing the agricultural productaccording to default amounts in the event of a terminal failure of thesystem. The terminal failure may occur for a single valve, a set ofvalves, or for the entire system. In this manner, the system can includea “limp-home” feature that allows an operator to continue to treat afield even when errors have been detected. The limp-home features can beautomatically enabled upon the detection of errors or can be enabledmanually by the operator.

In one embodiment, physically connected groups of valves or nozzles arewired to open and close in association with a conventional sprayersystem being used for limp-home or emergency bypass mode to facilitatethe starting and stopping of conventional flow, thereby permitting theoperator to continue working unencumbered by the system. For example,actuators such as pumps, valves, etc. and sensors such as pressuresensors and flowmeters are wired to communicate directly with theconventional sprayer system being used for limp-home or emergency bypassmode to facilitate the control of flow by conventional means, when thesystem is being retrofitted onto a preexisting system.

In still another embodiment, the individual flow from each valve ornozzle may also be controlled by a remote control and/or wirelessdevice. For instance, in one embodiment, individual nozzles or valvesmay be inspected for damage, wear or other performance relatedmalfunctions including accuracy calibration, location verification andother system setup parameter verifications with the operator beingphysically located near the valve in question. In this manner, thevalves and nozzles can be inspected and can be tested without theoperator having to physically return to the main control consoletypically located in the vehicle pulling the boom in order to manuallyactuate the valve controllers each time a different valve or collectionof valves is inspected.

These and other modifications and variations to the present inventionmay be practiced by those of ordinary skill in the art, withoutdeparting from the spirit and scope of the present invention, which ismore particularly set forth in the appended claims. In addition, itshould be understood that aspects of the various embodiments may beinterchanged both in whole or in part. Furthermore, those of ordinaryskill in the art will appreciate that the foregoing description is byway of example only, and is not intended to limit the invention sofurther described in such appended claims.

What is claimed:
 1. A system for applying liquids, the systemcomprising: a plurality of individually controlled valves that areconfigured to emit liquid at an overall application rate based on volumeper time; and a controller in communication with each of the valves, thecontroller being configured to receive a plurality of flow relatedindividual control values for each valve, the controller being furtherconfigured to determine a flow factor for each valve based on theindividual control values, wherein the controller is configured to varythe rate at which the liquid is emitted from each valve as the flowfactor for each valve changes without changing the overall applicationrate.
 2. The system of claim 1, wherein the rate that the liquid isemitted from each valve is based on a normalized duty cycle percentage,the controller being configured to determine the normalized duty cyclepercentage for each valve based on the flow factor for each valve and acorporate duty cycle percentage.
 3. The system of claim 2, wherein aminimum duty cycle percentage is set for each of the plurality ofvalves, the controller being configured to assign the minimum duty cyclepercentage for one of the plurality of valves when the normalized dutycycle percentage determined for such valve is less than the minimum dutycycle percentage.
 4. The system of claim 1, wherein the controller isconfigured to close one of the plurality of valves when at least one ofthe individual control values for such valve is equal to zero.
 5. Thesystem of claim 1, wherein the flow related individual control valuescomprise unitless values that are proportional to each other and arebased upon the amount of liquid that is emitted by each valve for acertain operating condition or parameter.
 6. The system of claim 1,wherein one of the flow related individual control values comprises atleast one of a valve turn radius for each valve or a swath overlap. 7.The system of claim 1, wherein one of the flow related individualcontrol values is based upon irregular valve spacing.
 8. The system ofclaim 1, wherein one of the flow related individual control valuescomprises an increased or decreased application rate due to at least oneof a vehicle affect, a field affect or a vegetative affect.
 9. Thesystem of claim 1, wherein one of the flow related individual controlvalues comprises a location of each valve on a global information systemprescription map or on a field boundary map.
 10. The system of claim 1,wherein one of the flow related individual control values comprises atleast one of a value related to soil fertility, soil conductivity, orvalve pressure.
 11. The system of claim 1, wherein the plurality ofvalves comprises pulse width modulated valves, the controller beingconfigured to control at least one of the plurality of pulse widthmodulated valves in conjunction with a non-pulsating valve.
 12. Thesystem of claim 1, wherein the plurality of valves are mounted on a boomthat is configured to be traversed across a field by a vehicle.
 13. Thesystem of claim 1, further comprising a rate controller and a flowsensor communicatively coupled to the controller, wherein a flow signaltransmitted by the flow sensor is modified by the controller based onthe flow factors, the modified flow signal being transmitted to the ratecontroller in order to maintain the overall application rate.
 14. Amethod for applying liquids using a plurality of individually controlledvalves, the method comprising: receiving a plurality of flow relatedindividual control values for each valve of the plurality of valves, theplurality of valves being configured to emit liquid at an overallapplication rate based on volume per time; determining a flow factor foreach valve based on the individual control values for each valve; andvarying a rate at which the liquid is emitted from each valve as theflow factor for each valve changes without changing the overallapplication rate.
 15. The method of claim 14, further comprisingdetermining a normalized duty cycle percentage for each valve based onthe flow factor and a corporate duty cycle percentage, wherein varying arate at which the liquid is emitted from each valve as the flow factorfor each valve changes comprising operating each valve at the normalizedduty cycle percentage determined for such valve.
 16. The method of claim15, wherein a minimum duty cycle percentage is set for each of theplurality of valves, wherein operating each valve at the normalized dutycycle percentage determined for such valve comprises operating one ofthe plurality of valves at the minimum duty cycle percentage when thenormalized duty cycle percentage determined for such valve is less thanthe minimum duty cycle percentage.
 17. The method of claim 14, whereinthe individual control values comprise unitless values that areproportional to each other and are based upon the amount of liquid thatis emitted by each valve for a certain operating condition or parameter.18. The method of claim 14, wherein determining a flow factor for eachvalve based on the individual control values for each valve comprisescontinuously determining the flow factor for each valve duringapplication of the liquid.
 19. The method claim 14, wherein theplurality of valves are mounted on a boom that is configured to betraversed across a field by a vehicle.